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Seismicity of the Earth 1900-2010 eastern margin of the Australia plate

Open-File Report 2010-1083-I

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Abstract

The eastern margin of the Australia plate is one of the most seismically active areas of the world due to high rates of convergence between the Australia and Pacific plates. In the region of New Zealand, the 3,000 km long Australia-Pacific plate boundary extends from south of Macquarie Island to the southern Kermadec Island chain. It includes an oceanic transform (the Macquarie Ridge), two oppositely verging subduction zones (Puysegur and Hikurangi), and a transpressive continental transform, the Alpine Fault through South Island, New Zealand. Since 1900, there have been 15 M7.5+ earthquakes recorded near New Zealand. Nine of these, and the four largest, occurred along or near the Macquarie Ridge, including the 1989 M8.2 event on the ridge itself, and the 2004 M8.1 event 200 km to the west of the plate boundary, reflecting intraplate deformation. The largest recorded earthquake in New Zealand itself was the 1931 M7.8 Hawke's Bay earthquake, which killed 256 people. The last M7.5+ earthquake along the Alpine Fault was 170 years ago; studies of the faults' strain accumulation suggest that similar events are likely to occur again.

Study Area

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Seismicity of the Earth 1900-2010 eastern margin of the Australia plate
Series title:
Open-File Report
Series number:
2010-1083
Chapter:
I
Year Published:
2011
Language:
English
Publisher:
U.S. Geological Survey
Publisher location:
Reston, VA
Contributing office(s):
Geologic Hazards Science Center
Description:
1 Plate: 24.01 x 35.70 inches
Time Range Start:
1900-01-01
Time Range End:
2010-12-31
Country:
American Samoa;Fiji;New Caledonia;New Zealand;Samoa
Projection:
Albers Equal Area Conic
Scale:
8000000
Additional Online Files(Y/N):
N